Steroids



United States PatentjO STEROIDS John A..Hogg, Kalamazoo Township, Kalamazoo County, Philip F. Beal, Portage Township, Kalamazoo County, and Alan H. Nathan and Frank H, Lincoln, Jr., Kalamazoo Township, Kalamazoo County, Mich., assignors i to The Upjohn Company, Kalamazoo, Mich., acorporation of Michigan z s I Application December 17,1954, Serial No. 476,057-

3 Claims. 01. 260-3911 No Drawing.

This invention relates to novel lower-alkyl 3-keto- 4,9( l1),17(20)-pregnatriene-21-oates. This application is a continuation-in-part of the copending application S..N. 346,274, filed April 1, 1953. t

It is an object of the present invention to provide the novel lower-alkyl 3-keto-4,9 1 1 17 20) -pregnatriene-2loates. Other objects will be apparent to those skilled in the art to which this invention pertains.

The novel compounds of the present invention are useful in the production of known and physiologically active steroids, including 9( l l -dehydrohydrocortisone acetate and 9a-fluorohydrocortisone acetate. The novel compounds and a method for their production may be illustrated as follows: I

Esterifying a lower-alkyl .3 keto-11m hydroxy-4,17(20)- pregnadiene-Zl-oate (I), claimed in the copending application of Hogg et al., S. N. 319,173, filed November 6, 1952, with paratoluenesulfonyl chloride is productive of a lower alkyl 3-keto-11u-tosoyloxy-4,l7(20)-pregnadiene- 2l-oate (II),claimed in the copending application of Jackson et al., S. N. 476,060 (Case 820). Detosylation of this compound in refluxing collidine is productive of the lower-alkyl 3-keto-4,9(1 l 17 (20) -pregnatriene-21- oates (III), of the present invention. The preparation of 1 the novel compounds of the present invention is disclosed .glycol ketalwhich, when reducedwith lithium aluminum the sodium enolate of l1a-hydroxy-2l-ethoxyoxalyl- 2,771,475 Patented Nov. 20,1956

hydride infether, is converted to the 3-ethylene glycol ketal of 2l-hydroxy- 4,9( 1 l 17 (20) -.pregnatriene-3-one. Hydrolysis of the 3-ethylene glycol ketal in aqueous acetone containing hydrochloricacid to regenerate the 3- kettrfgroup followed by acetylation of the 2l-hydroxy group'with acetic anhydride is productive of 21-acetoxy- 4,9(l1),17(20)-pregnatriene-3-one. Oxidative hydroxylation of this compound with hydrogen peroxide in the presence of 'a catalytic amount of osmium tetroxide is productive of the known l7u-hydroxy-21-acetoxy-4,9(11)- ,pregnadiene-3,20-dione"which can be converted to the phsiologically active 9u-fluorohydrocortisone acetate by known methods.

Alternatively, the lower-alkyl 3-keto-4,9(11) ,17(20)- pregnatriene-2l-oates of the present invention canbe reacted with N-bromoacetamidqin the presence of a mineral acid and water, to produce hydrobromous acid which adds tothe 9(ll)-dou ble bond to produce a lower-alkyl 3 keto 9a bromo-ll/3-hydroxy-4,l7(20)-pregnadiene- ZI-oate. Reaction of this compound with potassium acetatein methanol is productive of a lower-alkyl 3-keto- 9: l'l-fl-oxido-4,l7(2 0)-pregnadiene-2l-oate which is converted, with hydrogen fluoride in chloroform, to a loweralkyl 3-keto-9u-fluoro-l 1B-hydroxy-4, l 7 (20 -pregnadiene- 2l-oate. Ketalization of the 3-keto group of this conipound with ethylene glycolfollowed by reduction of the ,21-carboxylic acid ester group with lithium alminum hydride in ether is productive of the 3-ethylene glycol ..oxy,4, l7(20)-pregnadiene-3-one which is'converted, by

oxidative-hydroxylation with N-rnethylmorpholine oxide peroxide in the presence of a catalytic amount of osmium tetroxide, to the known 9a-fluorohydrocortisone acetate.

The novel compounds of the present invention include those represented by FormulaIII wherein the lower-alkyl .group is, for example, methyl, ethyl, propyl, isopropyl,

butyl, isobutyl, amyl, 2-methylbutyl, 3-methylbutyl, hexyl, heptyl, or octyl, prefer ably methyl or ethyl.

The following examples and preparations are illustrative of the products of the present invention, and a process for their. production and use, but

are not to be construed as limiting.

' PREPARATION 1 1.,-METHYL 3-KETo-1 la-rmmoxy- 4,'17 (20) -PREGNAninNE-21-0ATE :To-a stirred solution of 22.60 grams (0.05 mole) of progesterone (U. S. 2,683,724) in 550 milliliters of methanol was added dropwise sixteen grams (0.1' mole) of bromine. Tov the resulting solution of 29.4 grams (0.05 mole) of 1Iva-hydroxy-Z1,21-dibromo-21-ethoxyoxalylprogesterone was added. a solution of 16.5 grams (0.3 mole) of sodium'methoxide in 500 milliliters of methanol. The reaction mixture was maintained at about 25 degrees centigrade for sixteen hours whereafter anfequal .volume of water was added thereto and the whole was extracted with about equal portions of first benzene and then two portions of methylene chloride.

The combined extracts were dried with anhydrous sodium sulfate and thereafter distilled to remove the solvent therefrom. The distillation residue was dissolved in500 milliliters of methylene chloride and chromatographed over 875 gramsof Florisil synthetic magnesium silicate. The column was developed with 1,250-milliliter portions of solvents of the following composition and order: four of methylene chloride plus five percent acetone, four of methylene. chloride plus ten percent acetone,: four of methlene, chloride plus fifteen; percent acetone, two-9f methylene chloride plus twenty percent acetone, and finally, two of acetone. The methylene chloride plus ten percent acetone eluates and the first methylene chloride plus fifteen percent acetone eluate were combined and thesolvent distilled therefrom. The seven, grams of distillation residue was recrystallized from a mixture of ethyl acetate and Skellysolve B' hexane hydrocarbons to yield crystalline methyl 3-keto-11'a-hydroxy-4,17(20-) pregnadiene-Zl-oate melting at 205 to 21.0 degrees centigrade.

Analysis:

Calculated for C22H3004! C, 73.75; H. 8.48 Found: C, 73.77; H, 8.38

Similarly, other lower-alkyl 3-keto-11 a hydroxy-4,17- (-)-pregnadiene-2l-oate acid esters are prepared wherein the lower-alkyl group is methyl, propyl, butyl, amyl, hexyl, heptyl, octyl, or the like, by replacing the sodium tion by the corresponding alkali-metal alkoxide in an alkanol.

Alternatively, the thus-produced methyl 3-keto-1-1a-hymethoxide in methanol used in the above-described reacdrox'y-4,17(20)-pregnadiene-21-oate can be saponified to g tained: at about 25 degrees centigrade for 72 hours. The

mixture was then poured into 100 milliliters of cracked ice and water and the precipitated product separated from the aqueous phase by filtration. The precipitate was dissolved in 75 milliliters of chloroform and the solution washed with fifty milliliters ofwater. The chloroform solution was then dried over anhydrous sodium sulfate and the chloroform then evaporated.- The-residue was dissolved in 25 milliliters of'chloroformand poured over a chromatographic column of 75 grams of Florisil synthetic magnesium silicate. The column was developed with 100-milliliter portions of solvents of the following composition and order: Three of Skellysolve Bhexane hydrocarbons plus five percent acetone. Three of Skellysolve B plus ten percent acetone. Three of Skellysolve B plus twenty percent acetone. Three of Skellysolve B plus thirty percent acetone-and twoof acetone. The Skellysolve. B plus thirty percent, acetone eluted 1.262 grams, ayield of 88.5 percent of the theoretical, of methyl 3-keto-11a,-(para toluenesulfonyl xy)- 4,17(20)-pregnadiene-21-oate which, after crystallization from a mixture of 25 milliliters of hot acetone. and. '75 milliliters. of Skellysolve B, weighed 1.03 grams, melted at 149 to 153 degrees centigrade, had'anoptical rotation, [11], of plus seventy degrees in acetone andjthe, analysis below.

Calculated for CzsHsgsOrsS: C, 67.96; H,"7;08; S; 6.25. Found: C, 68.08; H, 754; S; 6.25.

Similarly, other 3 -keto-11u-(para-toluenesulfonyloxy)- 4, 17(20) -pregnadiene-21-oates are prepared; by. substituting other esters of 3-keto-11ot-hydroxy 4,17 (20)-pregnadiene-20-oic acid in the esterification reaction with paratoluenesulfonyl chloride, e. g., alkyl estersandpreferably lower-alkyl esters, for example, the ethyl,,propyl, butyl, amyl, hexyl, heptyl, or ester.

(para toluenesulf'onyloxy) -.4,17(20)- -.pregnadiene-21-,

oatein tenmilliliters of'collidine was refluxed1at172 degreescentigradeforthirty minutes. The reactionmixwith -milliliters of diethyl ether. The collidine was removed from the ether by washing with cold five percent hydrochloric acid. The ether layer was then dried over anhydrous sodium sulfate, filtered and the ether then distilled. There was thus obtained 0.316 gram of methyl 3- keto- 4,9(11),17(20) -pregnatriene-2l-0ate which, after crystallization from a mixture of acetone and Skellysolve B, weighed 0.31 gram, a yield of 93.5 percent of the theoretical, melted at to degrees centigrade and had the analysis below.

Calculated. for CzzHzaOa: C, 77.61; H, 8.28. Found: C. 77.58; H, 8.19.

Following the procedure described in Example 1, methyl 3-keto-4,9(l1-),17(20)-pregnatriene-2l-oate can be prepared by the reaction of methyl 3-keto-11a-(paratoulenesulfonyloxy) 4',17 (ZOJ- regnadiene-ZI-oate with sodium acetate in boiling glacial acetic acid, refluxing methanol, or absolute ethanol, five percent ethanolic potassium hydroxide, or potassium acetate in boiling aqueous acetone, sodium formate in refluxing methanol, or similar reagent.

Similarly, substituting another lla-sulfonyloxy ester of methyl3' keto- 11oz hydroxy-4,17(20)-pregnadiene-21- oate, for example, the benzenesulfonate, the 2,4,6-trimethylbenzenesulfonate, 'the p-phenylbenzenesulfonate, methyl'sulfonate, etc, there is also produced methyl 3- keto-4,9 1'1 17 (20)'-pregnatriene-2l-oate.

Other esters of 3-keto-4',9 1 1 17 (20)-pregnatriene-21- oic acid wherein the ester group is, for example, aralkyl, alkaryl, or preferably lower-alkyl; e. g., ethyl, propyl, butyl, amyl, hexyl, heptyl, octyl, are prepared by substituting the corresponding esters of 3-keto-1la-(para-toluenesulfonyloxy),-4;17(20)-pregnadiene-21-oic acid or other llu-sulfonyloxy ester of an alkyl 3-keto-l1ot-hydroxy- 4,l7(20)-PI'eg11adl@l1B?21?Oflt6 in the reaction described in Example 1 or the paragraph following.

EXAMPLE 2 Ethyl 3-ket0,-4,9 (1 1 .)',17 20 -pregnatriene-21 -0ate Following the procedure described in Example 1, ethyl 3 keto-l1a-(para-toluenesulfonyloxy)-4,l7(20)-pregnadiene-21-oate is converted to ethyl 3-keto-4,9(11),17- (20)-pregnatriene-21-oate.

The following reactions are illustrative of a method for the conversion of the novel compounds of the present invention to known and/or physiologically active steroids.

Methyl 3-keta-9a-bromo-1 1p-hydroxy-4J 7 (20 -pregnad iene-Zl -0ate To a solution of 3.40 grams (0.010 mole) of methyl 3-keto-4,9(11),17(20)pregnatriene-21-oate in 120 milliliters of dioxane were added with stirring 1.78 grams (0.013 mole) of N-bromoacetamide and'twenty milliliters of a 25 percent aqueous solution of perchloric acid. Stirring was continued for ten minutes and one gram of sodium sulfite in 300 milliliters of water was then added. The mixture was thoroughly extracted with methylene chloride and the methylene-chloride extract was washed successively withtcold aqueous sodium bicarbonate and water, driedwith anhydroussodiurn sulfate, and the methylene chloride thendistilled at reduced pressure. The residue wast dissolved in benzene andpoured over a chromatographic.- columnof grams of Florisil synthetic magnesium silicate. The column was developed with 300-milliliter proportions of solvents ofthe following composition-and order: Nineof Skellysolve B hexane hydrocarbons plhsfivepercent acetone, seven of Skellysolve B plus 715 percent acetone, five of Skellysolve B plus ten percent acetone and oneof acetone. The Skellysolve B plus 7.5 percent acetone eluate contained the methyl 3' keto-9a-bromo-1 1 B-hydroxyA, 17 (20 -pregnadiene-21- oate-which, after;crystallization-from a mixture of acetone and Skellysolve B,'weighed 2.53 grams, ayield of 58 percent of the theoretical, and melted at 105 to 108 degrees centigrade. Recrystallization of this product from the same solvent mixture raised the melting point to 108 to 109 degrees centigrade (decomposition). Infrared spectrum analysis was consistent with the structure.

Methyl 3-ket0-9:11-B-oxid0-4,1 7 (20) -pregnadiene-21-0ate A mixture of 2.53 grams (5.78 millimoles) of methyl 3 keto-9a-bromo-1 1fl-hydroxy-4, l7(20)-pregnadiene-21- oate, three grams of anhydrous potassium acetate and 100 milliliters of absolute methanol was heated at the refluxing temperature of the mixture for 2.5 hours. The cooled solution was then diluted with two volumes of water and extracted thoroughly with methylene chloride. The methylene chloride extract was dried and then the solvent evaporated therefrom at reduced pressure. The residue was dissolved in benzene and then poured over a chromatographic column of 100 grams of Florisil synthetic magnesium silicate. The column was developed with 200- milliliter portions of solvents of the following composition and order: Nine of Skellysolve B plus five percent acetone, five of Skellysolve B plus 7.5 percent acetone, five of Skellysolve B plus ten percent acetone, and one of acetone. The Skellysolve B plus five percent acetone eluates contained 1.24 grams, a yield of 54 percent of the theoretical, of methyl 3-keto-9:11- 8-oxido-4,17(20)- pregnadiene 21 oate which, after crystallization from Skellysolve B containing a trace of acetone, yielded heavy needles melting at 123.5 to 125 degrees centigrade and having an optical rotation [061D in chloroform of plus 48 degrees and the analysis below.

Calculated for C22H2s04: C, 74.13;'H, 7.92. .Found: C, 74.33; H, 7.83.

Methyl 3-ket0-9a-flu0r0-11,B-hydroxy-4J 7 (20 -pregnadiene-ZI -0ate A solution of four grams (1.12 millimoles) of methyl 3-keto-9: 1 1-fi-oxido-4, 17 (20) -pregnadiene-21-oate in fifty milliliters of alcohol-free chloroform was cooled to zero degrees centigrade. To the cooled solution was added 25 milliliters of a cold solution of anhydrous hydrogen fluoride in alcohol-free chloroform whereupon a red color developed. The solution was stored at minus fifteen degrees centigrade for four hours with occasional stirring. The solution was then washed with aqueous sodium bicarbonate and then with water. The washed chloroform solution was dried and then distilled to dryness. The partially crystalline residue was dissolved in benzene and poured over a column of 200 grams of Florisil synthetic magnesium silicate. The column was developed with ZOO-milliliter portions of solvents of the following composition and order: Ten of Skellysolve B plus five percent acetone, five of Skellysolve B plus 7.5 percent acetone, five of Skellysolve B plus ten percent acetone, and one of acetone. The Skellysolve B plus 7.5 percent acetone eluates contained the methyl 3-keto-9a-fluoro-11p-hy droxy-4,17 (20)-pregnadiene-21-oate, which, after crystallization from a mixture of acetone and Skellysolve B, melted at 245 to 247 degrees centigrade, had an infrared spectrum absorption consistent with the structure and the analysis below. The Skellysolve B plus five percent acetone eluates contained 1.40 grams of starting steroid.

Calculated for C22H29FO4: C, 70.19; H, 7.76; F, 5.05. Found: c, 70.28; H, 7.71; F, 4.86.

The 3-ethylene glycol ketal of methyl 3-ket0-9u-flu0r0- 11fl-hydr0xy-4,17(20)-pregnadiene-21-0ate A mixture of 430 milligrams (1.4 millimoles) of methyl 1 '3 keto-9a-fluoro-l1fl-hydroxy-4,17(20)-pregnadiene-21- oate, three milliliters of ethylene glycol, 100 milligrams of para-toluenesulfonic acid monohydrate and fifty milliliters of anhydrous benzene was heated at the refluxing washed with aqueous sodium bicarbonate and then with water, and distilled at reduced pressure to dryness. The crude crystalline residue consisted essentially of the 3- ethylene glycol ketal of methyl 3-keto-9a-fluoro-11B hydroxy-4, 17 (20) -pregnadiene-21-oate.

The 3-ethylene glycol ketal of 9ot-flu0ro-1113,21-dihydroxy- 4,1 7-pregnadiene-3-0ne The :crude crystalline ketal obtained above was dissolved in 25 milliliters of benzene and then added drop- Wise to a stirred suspension of 0.5 gram of lithium aluminum hydride and fifty milliliters of ether. After the addition of the benzene solution was completed, the stirring was continued for 1.5 hours. The excess lithium aluminum hydride in reaction mixture Was then decomposed by the dropwise addition of five milliliters of ethyl acetate. Ten milliliters of water was then slowly added to the mixture followed by 25. milliliters of a solution of five milliliters of concentrated hydrochloric acid and twenty milliliters of water. The benzene layer wasseparated and washed with an aqueous solution of sodium bicarbonate followed by water. The benzene solution was then dried and distilledto dryness to leave a distillation residue consisting essentially of the 3-ethylene glycol ketal of 9a fluoro-l1,8,21-dihydroxy-4,17(20)-pregnadiene-3-one.

9ot-flu0r0-1 1 8,21 dihydroxy-4,1 7(20 -pregnadiene-3-0ne The crude 3-ethylene glycol ketal of 9a-fluoro-11B,21- dihydroxy-4,17(20)pregnadiene-3-one, obtained from the distillation residue above was dissolved in 35 milliliters of acetone. To the solution was added 5 milliliters of a 1.0 N solution of sulfuric acid and the acidic mixture maintained with stirring at about 25 degrees centigrade for six hours. Water was then added to the mixture. The aqueous mixture was extracted with methylene chloride and the methylene chloride extract then washed with aqueous sodium bicarbonate followed by water.

The extract was dried and the solvent distilled at reduced pressure. The residue was dissolved in a mixture of benzene and methylene chloride and poured over a chromatographic column of fifty grams of Florisil synthetic magnesium silicate. The column was developed with -milliliter portions of solvent of the following composition and order: five of Skellysolve B plus 7.5 percent acetone, seven of Skellysolve B plus ten percent acetone, five of Skellysolve B plus fifteen percent acetone, five of Skellysolve B plus twenty percent acetone and one of acetone. The Skellysolve B plus fifteen percent acetone eluates contained 190 milligrams of product. Trituration of a portion of this product with ether followed by crystallization from a mixture of ethyl acetate and ether gave fine needles of 9a-fiuoro-11fi,21-dihydroxy-4,17(20)-pregnadiene-3-one melting at 202.5 to 204 degrees centigrade and having the analysis below:

Calculated for C21H29F0s: F, 5.45. Found: F, 5.67, 5.55.

9a-flu0r0-11p-hydr0xy-21-acet0xy-4,1 7(20) pregnadiene-3-one Crude 9m-fluoro 11,8,21 dihydroxy 4,17 (20) pregnadiene-B-one, obtained from the chromatographic column described above, was dissolved in a mixture of five milliliters of acetic anhydride and five milliliters of pyridine. The solution was maintained at about 25 degrees centigrade for about sixteen hours and then poured into a mixture of ice and water. The gummy precipitate was extracted with methylene chloride and the extract then washed successively with ice cold dilute aqueous hydrochloric acid, cold aqueous sodium bicarbonate and finally with cold water. The methylene chloride solution, after drying, was poured over a chromatographic colum of 75 grams of Florisil synthetic magnesium silicate. The column was developed with -milliliter portions of the following composition and order: five of Skellysolve B plus five percent acetone, eight of Skellysolve B plus 7.5 percent acetone, five of Skellysolve B plus ten percent acetone and one of acetone. The Skellysolve B plus 7.5 percent acetone eluates contained 9a-fluoro-11B-hydroxy- 2l-acetoxy-4,17(20)-pregnadiene-3-one, a portion of which, after crystallization from a mixture of acetone and Skellysolve B, melted at 205 to 207.5 degrees centigrade and had the analysis below.

Calculated for C23H31FO4: F, 4.87. Found: F, 4.24.

Approximately 125 milligrams of impure 9a-fluoro-11- p-hydroxy-2l-acetoxy-4,17(20)-pregnadiene 3 one, obtained from the chromatographic column described above, was dissolved in eight milliliters of dry tertiary butyl alcohol containing one milliliter of dry pyridine. The solution was mixed at room temperature with stirring with 0.6 milliliter of a solution of 0.125 N solution of N- methylmorpholineoxide peroxide prepared by the reaction of N-methylmorpholine with two molar equivalents of anhydrous hydrogen peroxide, in dry tertiary butyl alcohol. To this mixture was added five milligrams osmium tetroxide and the solution stirred for 4.5 hours at about 25 degrees centigrade. Aqueous sodium sulfite was then added and the mixture extracted with methylene chloride. The extract was washed with water, dried and the solvent distilled. The distillation residue was dissolved in benzene and poured over a chromatogarphed column of fifteen grams of Florisil synthetic magnesium silicate. The column was developed with SO-milliliter portions of solvents of the following composition and order: five of Skellysolve -B plus 7.5 percent acetone, five of Skellysolve B plus ten percent acetone, five of Skellysolve B plus fifteen percent acetone, three of Skellysolve 3 B plus twenty percent acetone, and one of acetone. The Skellysolve B plus fifteen percent acetone eluates were distilled to dryness leaving 47 milligrams of 9a.-fiuoro- 11B,17a-dihydroxy-21-acetoxy-4 -pregnene 3,20 dione (9a-fluorohydrocortisone acetate) melting at 195 to 200 degrees centigrade.

It is to be understood that the invention is not to be limited to the exact details of operation or exact compounds shown and described, as obvious modifications and equivalents will be apparent to one skilled in the art, and the invention is therefore to be limited only by the scope of the appended claims.

We claim:

1. Lower-alkyl 3 keto 4,9(l1),l7(20)-pregnatriene- 15 2l-oate having the formula:

0 O O-lOwer-alkyl CH CH3 I 2. Methyl 3-keto-4,9(l1),17(20)-pregnatriene-2l-oate. 3. Ethyl 3 keto-4,9(11),17 (20)-pregnatriene-21-oate.

References Cited in the file of this patent UNITED STATES PATENTS Re. 22,941 Reichstein Nov. 25, 1947 2,695,906 Hogg Nov. 30, 1954 

1. LOWER-ALKYL 3 - KETONE -4,9(11),17(20)-PREGNATIENE21-OATE HAVING THE FORMULA: 